For the first time in 22 months, the Roanoke and New River valleys are under a winter storm watch as the region rides the line Wednesday between snow, sleet and freezing rain.
The National Weather Service cited possible snow accumulations of 2 to 7 inches and ice accretions of up to two-tenths of an inch in issuing the watch, which is the first to cover the U.S. 460 corridor from Roanoke to the Blacksburg/Christiansburg area since prior to a similar Feb. 20, 2019, snow-to-ice event. Last winter produced only brief, light snowfall and minor icing episodes not intense or widespread enough for winter storm watches or warnings.
The snow range is rather wide because there remains considerable uncertainty about which precipitation types will occur for how long. More sleet would reduce snowfall totals and a mostly freezing rain event could almost eliminate the snow. Generally speaking, snowfall will be greater north and west of Roanoke, while sleet and ice will be greater to the south and east.
Whichever way it goes, it’s likely to be a wintry mess on many roadways Wednesday morning, as precipitation is expected to begin in the predawn hours and continue through much of the day. There could also be scattered power outages in areas where freezing rain dominates, weighing down tree limbs and power lines with ice.
The setup responsible for this winter storm threat involves a low-pressure system approaching from the southwest the reforming along the East Coast. Meanwhile, high pressure over southeast Canada will press cold air southward, trapped against the mountains, ensuring precipitation types are wintry not merely wet.
The heaviest snow will track well north of our region, with foot-plus amounts possible from eastern West Virginia across Northern Virginia and northeastward.
Some snow showers may linger into Wednesday night and early Thursday, with cold and dry weather returning for late week. High temperatures in the 40s Thursday and Friday will help melt whatever snow and/or ice collects.
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